Filter



Aug. 6, 1929. c. w. MCKINLEY FILTER Filed Feb. 5, 1927 Patented Aug.` 6, y

UNITED STATES imarlsla'r oFFlca.V

CHARLES W. MCKINLEY, FIINT, MICHIGAN, ASSIGNOR T A C SPARK IPLUG O0M' PANY, OF FLINT, MICHIGAN, A COMPANY OF MICHIGAN.

. FILTER.

Application led February 5, 1927. Serial'No. 166,162.'

The invention relates to filters and more particularly to a filtering element formed of iexible material, such as cloth., The object of the invention is to provide a filter element or filter body in which Aare combined the features of a very large area of filtering surface in a relatively small volume together with a convenient shape for mounting in a receptacle or holder.

In the accompanying drawings illustrating one embodiment of the invention, Fig. 1 is a side view, partly broken away, showing the filtering element prior to its assembly in operative position.

Fig. 2 is a vertical section on line 2 2 of Fi .1.

ig. 3 is an elevation, with parts broken away, showing the filter body assembled in a holder, and Flg. 4 is a horizontal section on lme 4-4 of F1 3. y I

Reerring to the drawings, 5 indicates a lter element which has somewhat of the characteristics of a bag and to which, there-i.

fore, such term may, for convenience, be here-s inafter applied. This bag is constituted, in the form shown, of a sheet of fabric, folded at the lower edge, as at', and havin its ends closed by sewing the two layers of `abrio together, as at 7. The top of the bag is also closed by sewing the edges together, as at 8,

f except fora restricted opening at 9 of such size as to engage closely around the neck of a suitable fitting 10 whereby fluid to b e ltered may be introduced into the bag. The inlet opening 9, in accordance with the presentv invention, is positioned at a point somewhat removed from the ends of the bag, preferably near the longitudinal center thereof, thereby providing a ltering area on each side of the inlet.

The bag is preferably divided into a plurality of parallel channels or pockets, as by longitudinal and parallel rows of stitches 11,

extending from the ends of the bag to points approximately below the inner ends of the top seams 8. The pockets 12 lthus formed, therefore, terminate approximately in registry with the opening 9 and communicate at their inner ends with'a central open passage 13 extending downward from the said opening. Lubricating oil or other material to beA filtered, if introduced at the opening 9 under pressure, vwill accordingly be free .to flow downward through the central passage between the inner ends of the seams 11, and

thence outward in the pockets 12 toward the ends of the bag.

" In practice, the filtering element, afterl being made in substantially flat form as shown in Fig. 1, will be secured around the opening 9 to the inlet fitting 10, which latter ma ,if desired, be providedrwith a perforated out et pipe 10 extending downwardly to any suitable dist-ance in the passa e 9. The bag is then folded over transverse y in line with the point where the fitting 10 is attached and rolled from the folded portion toward the ends. The filter body thus assumes the form of acylinder comprising two interleaved spi- Ials; with the opening approximately at' the `ax1s as shown in Fig. 4. It may be held in this form by any suitable binding means or may be inserted in a holder such as is illustrated in Figs. 3 and 4. The holder shown comprises a cylindrical cage 14 ofwire cloth, the ends of which are covered and enclosed by caps 15, 16, fitting over the ends of the cagel and held together by straps 17'. The fitting 10 extends beyond the end cap 15 in position to be connected to a` conduit leading from a source of material to be ltered, for example, the lubricant pump of an internal combustion engine. The filter body will, of course, be positioned in a receptacle whereby the purifed material discharged through the wallsl filtered is forced to pass through the walls without having to fiow very far through the interior passages or. channels. Thus a maximum filtering capacity is -maintained with a minimum resistance to flow'interiorly of the %Vhen the bag has been rolled into the form of the double spiral, as described, and the f spirally extending pockets 12 become filled with li uid under pressure, there will obviously e a tendency for the pockets to expand lnto an approximately elliptlcal cross- 4 section. Thus the distended portionof each.

pocketin one spiral end sect-ion will lie in contact with corresponding portions of the similar pocket in the other end section. The

'portions adjacent to the seams 11, however,

since they cannot be distended, will leave spiral channels on the outside of the bag between .successive turns of the spiral, as indicated at 19, whereby the filtered material may escape freely fromA any portion of the filtering surface to the outsideof the filter body. y

Another advantage which is `inherent in the filter comprising a spirally rolled flexible bag with spiral pockets or channels is that a fresh filtering surface is automatically provided over an extended period as the surface already in use becomes clogged. This is due to the fact that, as the bag is somewhat tightly rolled, a certain degree of pressure is required to cause the distention of the channels 12 throu hout their length. When the bag is new tte portions ad3acent the central passage 13 provide all the filtering capacity necessary and the portions more remote from the inlet remain inactive.d However, as the used portionsl become clogged with impurities, the slight increase 1n pressure causes the more remote portions of the pockets 12 to be opened up and fresh'filtering areas are brought into operation. Thus the filter may be made to operate with practically unreduced efficiency over an extended time and, furthermore, the pressure required to force vthe material through the filter remains relatively uniform throughout the entire effective life of the filtering element.

It will be understood that various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention, and therefore, I

do not wish to be restricted to the details above described except asrequired by the language of theappended claims inview of the prior art.

I claim:

l. A filtering element comprising a substantially flat fabric bagv having an opening in ter-mediate the ends the walls of the bag intermediate the edges being connected at intervals to form passages extending in opposite directions toward the ends from the vicinity of said opening.

2. A lterin element comprising a vsubstantially fiat abrio bag having an opening intermediate the ends, a passage communicating with said opening and extending across the bag, and pockets lopening from Said passage and extending therefrom toward the ends of the bag.

3. Structure as set forth in claim 2, including distending ,means in the inlet ends of said pockets.

4. A lterin .element comprising a substantially fiat abric bag of substantially recv tangular outline having an opening intermediate the ends on one edge, and means connecting the two walls of the bag in parallel lines endwise of the bag and on opposite sides of said opening, thereby forming a plurality of pockets or channels communicatmg with said opening and extending to the ends of the bag.

5. -A filterin elementcomprising a substantially Hat abric bag having the interior of the bag divided into aseries of passages, and distending means positioned in the inlet ends of said passages. i

6. Structure-as set forth in claim 5, said means including flexible loops having their ends positioned in adjacent passages. Y 7. A filter body comprising a substantially fiat fabric bag having an opening intermediate the endsanda series of'substantially parallel pockets extending in opposite directions from the vicinity of said opening to the ends, said bag being folded; transversely in the vvicinity of' said. opening andv rolled into a double spiral with the opening at the center.

8. Structure as set forth in claim 7, the opening being on one edge of the bag and the bag having a transverse passage communicating with the said opening and with which each of said pockets communicates.

9. A filter comprising, as a unit, a spirally wound bag having an inlet fitting at one end and a holder therefor, said holder, comprising end caps through one of which said fitting extends, a cage whose ends are covered by saidcaps, and straps connecting said caps.

10. A filter comprising, as a unit, a filtering lelement havin a pipe fittingat one end, and a holder there or, said holder comprising end caps through.I one'of which said' fittindgs ex-` tend, a per orate cage held between s ai caps,

mesme tending to the exterior of said holder whereby said element may be connected to an external 10 conduit, said assembly constituting a. unit adapted for insertion into or removal from a. filter receptacle.

In testimony whereof I' affix niy signature.

CHARLES W. MCmNLEY; 

